I was having trouble installing my MediaWiki for quite a while now.

Whenever I tried to complete the installation, I get this bug about “Fatal error: Class 'UnlistedSpecialPage' not found in /pathto/
mediawiki-1.5.3/includes/SpecialPage.php on line 28”

So, of course, I hunted up the bug entry on MediaZilla on the issue, but no dice. Eventually, I got desperate enough to go onto IRC, a place I've not visited for quite some time, and found Brion Vibber (going by the nick of brion) who solved the issue for me.

It seems that the Turck mmcache is the culprit here, as it hasn't been updated for a long time.

Removing it solves the issue!

Thanks, Brion!